Yamamoto ignored Itachi's actions as he took a step, appearing in front of Itachi and swinging his sword towards him.
Time Freeze
Amenotejikara
The next moment, time froze as Itachi replaced the Espada, Karin, Rukia, and the extra who were still within a few kilometres around him with the stones at the edge of Seireitei.
As for why not kill Yamamoto while time is paused or use his combo of killing Isshiki? Well, Itachi wanted to train a bit in Kenjutsu. However strong his strength is, his Kenjutsu is at most Kage to Super Kage level, not comparable to Yamamoto, a thousand-year-old man. So why not take this as an opportunity to learn?
Niddhogg Transformation — SWORD OF NIHILITY
With time still paused, Itachi summoned Niddhogg and transformed it into a black blade burning with black fire as if from Hell. Though this isn't Amaterasu flames but Nihility flames capable of nullifying all phenomena, like Yamamoto's flames or Ichibei's ability, to nothing.
Time Start
CLANGG
The moment time started, Yamamoto's sword was blocked by Itachi's Sword of Nihility. But, seeing this, all the captains as well as Yamamoto became extremely shocked.
You must know, Yamamoto, when he fought Yhwach's copy, was certain that anything that touched it would be annihilated, but here Itachi's sword didn't even chip a little.
"Let's continue, old man." With that, Itachi used force to push Yamamoto back and attacked at light speed.
CLANGG CLANGG CLANGG
For the next minute, Itachi and Yamamoto exchanged thousands of moves. Although Yamamoto's Kenjutsu was superior to Itachi's, Itachi surpassed Yamamoto in everything else, like hax, Spiritual Energy, Physique, and Speed.
BANG
With a final thrust, Yamamoto was sent flying backward, but he quickly stabilized himself. Although he had successfully blocked Itachi's attack without sustaining any damage, he wasn't pleased.
His eyes narrowed as he observed the monstrous improvement in Itachi's swordsmanship. His Kenjutsu had already reached the level of a Captain—and now, he was attempting to match Yamamoto himself.
Well, Itachi can just say that his copying ability isn't that inferior to Garou. With his divine Mangekyō Sharingan and Byakugan, he can copy S-rank jutsu after just watching it twice, and so can he copy Yamamoto's swordsmanship.
West – Nishi: Zanjitsu Gokui (Sunset Hell Robe)
Yamamoto, who was pushed back, didn't attack immediately but used his second Bankai attack as his entire body was covered with flames of 15 million degrees. Hundreds of meters around him, flames filled the entire area, capable of burning even a Kage-level ninja to ashes within seconds if caught by just a spark.
Conversion: Water
Itachi, facing all these, just snapped his fingers as all the fire turned into tens of millions of gallons of water, though it was quickly evaporating because of Yamamoto's Bankai.
Yamamoto, seeing this, tried once again, but the result was the same; most of the flames left his body and transformed into water.
"Is Old Man Yama at a disadvantage?" Shunsui, seeing this scene, was in complete disbelief. Yamamoto, when he fought in the Quincy war a thousand years ago, didn't even use his full strength and was invincible. Now, even without holding back, Yamamoto was pushed back.
"Karin, your Sensei is too strong." Ichigo, who had arrived beside Karin at some point, said with admiration. Although he wasn't very happy with Itachi's destruction of Seireitei, he still admired Itachi's and Yamamoto's strength.
South – Minami: Kaka Jūman'okushi Daisōjin
("Great Burial Ranks of the Ten Trillion Fire Dead")
Seeing his defense and attack useless, Yamamoto used his third ability. The moment Yamamoto muttered the somewhat too big name, the ground beneath him changed into scorched earth.
From the ground, skeletons and corpses started to emerge as the countless dead began to march towards Itachi.
"Truly interesting, the head of Shinigami is awakening and controlling the dead... But, it's not enough. Niddhogg, show him how it's done." As Itachi said this, he dropped the sword in his hand as it merged with the ground.
The next second, the entire Seireitei's ground became pitch black as, one after another, souls wearing black armour climbed onto the black ground.
"Yamamoto, you control them by heating the ashes of those you have slain, but you have killed too few... How many did you kill? Thousand... ten thousand... hundred thousand... million... ten million? Welcome to fight billions." As Itachi said this, more than a million souls roared in unison.
ROARRRRRR
The principles of Yamamoto's and Itachi's techniques are different. What Itachi did is simply let Niddhogg disintegrate into all the souls it devoured. But they aren't the weak, useless souls, as Niddhogg's powers are still within them, and they can group together whenever they are needed.
Itachi gained inspiration for this ability from Black Sperm of OPM, but unlike Black Sperm, who permanently lost that clone after its death, it won't happen here, as those slain souls can be reborn within the Nihility Sea, which covered the ground of Seireitei.
"Fuck... both these guys are evil!" Ichigo, on the other hand, seeing this world-ending scene, only had curses in his mouth. Although he had seen the evil of Soul Society like the situation of Rukongai and the class barrier of Soul Society but, now the Captain Commander of Soul Society has killed millions and is using their corpses for attacking.
"Ichigo, I advise you not to be brainwashed by these Shinigami.... Do you know why Quincy are so rare? It's because these Shinigami have tried to exterminate us twice." Uryu, hearing Karin's words, nodded heavily in recognition.... God knows why is he here rescuing a Shinigami with his life in danger.
Within a few seconds, all the corpses that Yamamoto controlled were killed by Niddhogg as, after completing their task, they once again merged to become a sword in Itachi's hand.
North – Kita: Tenchi Kaijin (Heaven and Earth Reduced to Ashes)
Hearing Yamamoto's words, Itachi knew that this fight was finally coming to an end. This is the strongest attack of Yamamoto and was able to slice Yhwach's copy in two.
The next second, Yamamoto, in fury, slashed towards Itachi.
Time Freeze
Inevitable Outcome
Amenotejikara × 2
Fuinjutsu: Soul Death
Time Start
SLAASSSHHHHH
Yamamoto, who had simply annihilated more than twenty centimetres of the opponent's body from stomach to waist, making the enemy a KitKat, paused behind the opponent.
---
Soul King Royal Palace
"Is Yamamoto using his Bankai?" Senjumaru, sensing the disturbance caused by Yamamoto's Bankai, said softly.
"It looks like the fight is over. But forcing him to use Bankai is indeed impressive." Tenjirō Kirinji, the healer of Squad Zero, sensing the Soul Society calming down within a few seconds, concluded that Yamamoto killed the enemy within seconds.
"It doesn't matter, as long as the enemy doesn't affect Soul King Palace, we have no need to interfere." Ichibei, hearing the conversation, said, smiling.
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